﻿76 
  W. 
  Foshag 
  — 
  Sulphohalite. 
  

  

  Art. 
  V. 
  — 
  Sulphohalite 
  from 
  Searles 
  Lake, 
  California; 
  1 
  

   by 
  Wm. 
  Foshag. 
  

  

  Sulphohalite 
  was 
  described 
  by 
  Hidden 
  and 
  Mackintosh 
  

   in 
  1888 
  and 
  its 
  composition 
  established 
  by 
  Penfield 
  in 
  

   1900. 
  At 
  the 
  time 
  Penfield 
  studied 
  this 
  mineral 
  only 
  

   four 
  specimens 
  were 
  known 
  and 
  so 
  far 
  as 
  the 
  writer 
  is 
  

   aware 
  none 
  have 
  been 
  reported 
  since. 
  2 
  It 
  is 
  interesting 
  

   to 
  note, 
  therefore, 
  that 
  three 
  more 
  crystals 
  have 
  been 
  

   found 
  in 
  material 
  in 
  the 
  U. 
  S. 
  National 
  Museum. 
  

  

  Sulphohalite 
  has 
  been 
  found 
  only 
  in 
  the 
  famous 
  

   Searles 
  Lake 
  (sometimes 
  called 
  Borax 
  Lake, 
  but 
  not 
  to 
  

   be 
  confused 
  with 
  Borax 
  Lake 
  in 
  Lake 
  Co., 
  Calif.) 
  in 
  San 
  

   Bernardino 
  Co., 
  California. 
  It 
  occurs 
  in 
  the 
  saline 
  

   layers 
  below 
  the 
  surface 
  crusts 
  and 
  in 
  close 
  association 
  

   with 
  hanksite. 
  Penfield 
  mentions 
  sulphohalite 
  grown 
  

   upon 
  hanksite 
  and 
  one 
  of 
  the 
  new 
  finds 
  had 
  a 
  small 
  frag- 
  

   ment 
  of 
  hanksite 
  attached 
  to 
  it. 
  

  

  The 
  first 
  crystal 
  found 
  in 
  the 
  new 
  lot 
  came 
  from 
  a 
  

   sample 
  labeled 
  " 
  Well 
  G75, 
  Searles 
  Lake, 
  75'-85'" 
  recently 
  

   turned 
  over 
  to 
  the 
  Museum 
  by 
  the 
  U. 
  S. 
  Geological 
  Sur- 
  

   vey 
  It 
  is 
  an 
  octahedron 
  showing 
  also 
  two 
  cubic 
  and 
  

   two 
  dodecahedral 
  faces. 
  It 
  measures 
  10mm. 
  and 
  weighs 
  

   •85gm. 
  A 
  small 
  fragment 
  chipped 
  from 
  it 
  dissolved 
  in 
  

   water 
  leaving 
  a 
  slight 
  residue 
  that 
  effervesced 
  with 
  acid 
  

   and 
  is 
  probably 
  calcite. 
  The 
  solution 
  reacted 
  for 
  both 
  

   chlorine 
  and 
  sulphate. 
  Its 
  index 
  of 
  refraction 
  measured 
  

   by 
  the 
  immersion 
  method 
  was 
  1455. 
  Specific 
  gravity 
  

   measured 
  on 
  a 
  Kraus-Jolly 
  balance 
  was 
  243. 
  In 
  order 
  

   to 
  place 
  the 
  mineral 
  definitely 
  as 
  sulphohalite 
  the 
  index 
  

   of 
  refraction 
  of 
  some 
  of 
  the 
  type 
  material 
  (U. 
  S. 
  Museum 
  

   No. 
  87376, 
  gift 
  of 
  S. 
  P. 
  Sadtler) 
  was 
  measured 
  and 
  found 
  

   to 
  be 
  identical 
  with 
  that 
  of 
  the 
  above 
  crystal, 
  1455. 
  A 
  

   second 
  and 
  smaller 
  crystal 
  was 
  found 
  in 
  the 
  same 
  lot. 
  It 
  

   weighed 
  -06gm. 
  and 
  showed 
  the 
  octahedron 
  and 
  dodeca- 
  

   hedron. 
  It 
  was 
  identified 
  by 
  its 
  index 
  of 
  refraction 
  and 
  

   lack 
  of 
  strong 
  saline 
  taste. 
  

  

  The 
  third 
  crystal 
  was 
  one 
  of 
  four 
  octahedrons 
  labeled 
  

   "Halite, 
  Searles 
  Lake, 
  Calif. 
  " 
  Its 
  yellowish 
  green 
  color 
  

   and 
  lack 
  of 
  strong 
  saline 
  taste 
  led 
  to 
  the 
  determination 
  

   of 
  its 
  index 
  of 
  refraction 
  which 
  proved 
  to 
  be 
  as 
  for 
  the 
  

  

  1 
  Published 
  with 
  the 
  permission 
  of 
  the 
  Secretary 
  of 
  the 
  Smithsonian 
  

   Institution. 
  

  

  2 
  Since 
  the 
  above 
  was 
  written 
  the 
  writer 
  's 
  attention 
  has 
  been 
  called 
  to 
  

   the 
  article 
  on 
  sulphohalite 
  by 
  Gale 
  and 
  Hicks, 
  in 
  this 
  Journal, 
  38, 
  273, 
  1914. 
  

  

  